7 Mag vs 7-300,worth The Effort?

[SporterII]

180+ gr. 7mm bullets for long range target are of interest.
Brass not being an issue, the Rem mag seems to be the easy button. Does the 300 case really make a worthwhile improvement?

 

[Tazman]

I have a 7-300WSM which shoots the 180 Berger at 2980 with H1000 all day long. Could easily push it harder but the node shoots better than .5 moa.

 

[Bradu]

300 win mag would gain you a fair amount of speed over the 7 rem mag. It is more work to start out but isn't too bad. I neck down in three steps using bushings for my 7-300 norma. I loaded up some rounds with a random load and hit 3 in a row at a mile last weekend. 3050 with a 195 Berger but I can run it faster than that. I will be doing load development soon to see where it will shoot good.

 

[knuckleballz]

I analyzed this very thing for a year and decided to go 7mm rem mag. If I can approach 3000fps with a 180 grain in 7mm rem mag with much lower cost and also have the factory ammo available in almost any city in America, it was the logical choice for me for hunting. But then again, I am building a speedy 22 creedmoor that will burn barrels like the 7-300.

 

[SporterII]

A 180+ @ near 3k in the 7mag is an easy button fore sure. If it shoots there. That's a large bet.

 

[davere]

West Texas Ordnance has a wildcat they make that's a necked down and improved 300 Norma. They're driving 180gr bullets in the 3300 fps range, and 195s to 3200. I have no idea what the barrel life is like, but the ballistics are pretty impressive... https://westtexordnance.com/7mm-300-norma-improved/ - I kinda want one, just because... LOL

 

[Bradu]

West Texas Ordnance has a wildcat they make that's a necked down and improved 300 Norma. They're driving 180gr bullets in the 3300 fps range, and 195s to 3200. I have no idea what the barrel life is like, but the ballistics are pretty impressive... https://westtexordnance.com/7mm-300-norma-improved/ - I kinda want one, just because... LOL

I would guess around 700 rounds but it all depends on how it's ran.

 

[Speedarino]

7-300WM has a lot to offer. Around 3000fps with Berger 195s, very manageable recoil, plenty of brass ( although Norma is scarce currently), 1000+ barrel life, 2000 yds+, and the ones I’ve seen shoot! Just had a recent discussion on load data regarding same.

 

[RTH1800]

I have used 7mm mags of about every size you can imagine for over 45 years.

7 300 is very good. 7rem is ok but about my last choice. 7 weatherby is good. I currently use 7/300 and a 7 on a necked down 375 H&H case not improved.

The 7 STW was not a fovorite but ok.

7/300 weatherby about same as STW.

My odd choice of 7/375 is based on being able to get one more round in magazine of magnum Mauser action. 4vs 3. Also having access to Mag Mauser actions and unlimited 375 brass.

Used it all over world for many years. Capacity identical to 7/300 win.

 

[SporterII]

Speedarino, where can I find that data?
ADG brass available in 300 and very soon in 7mag. 8.5tw barrel due soon.

 

[Hoyt7mm]

I've had fantastic luck with my 7-300wm shooting 195s under H1000. I am very tempted to get a barrel spun up for a 7-300PRC depending on how the 300 PRC takes off. Think it may be a good choice with added neck length, and shorter OAL (I currently have to single feed if I play with the 197 SMKs)

 

[Clownbuster]

I have a 7-300WSM which shoots the 180 Berger at 2980 with H1000 all day long. Could easily push it harder but the node shoots better than .5 moa.

This

 

[clcustom1911]

Speedarino, where can I find that data?
ADG brass available in 300 and very soon in 7mag. 8.5tw barrel due soon.

ADG 7 RemMag brass should be in Stock now.

 

[camotoe]

Idd build a 7prc and dump the belt

 

[Just Macca]

Not to hijack the thread, but how would it affects people’s decisions if a 23” barrel was the only restriction? Barrel life not a huge concern, with good brass being more of interest.
What would a 7-300 Norma push a 180 or 195gr bullet to in that short of a tube? Especially vs the 7 Rem Mag?
I’m guessing it would lose 75 - 100fps over the default 26”

 

[xdeano]

7-338 Norma mag
7-300 prc
7-300 rum
7 Saum.
Xdeano

 

[Milf Dots]

A 7mm-300prc or 7-300NM, driving 180-197gr bullets, sounds fascinating... Following this thread with great interest because of my fondness for 7mm magnums, which I alluded to in my thread:

https://www.snipershide.com/shootin...gnum-factory-cartridges.6968884/#post-8085455

 

[xdeano]

Personally, I think I'd go with a 7saum, for hunting applications. Shorter action, shorter bolt throw. The others are long actions. The 7-300 nm will require a larger bolt face and that might push you into are super mag type action. I know my 338nm is on a super mag action and its the parent.
I wouldn't use it for hunting unless it was a stationary position. Basically a canyon gun.

Just my thoughts.
Xdeano

 

[clcustom1911]

Not to hijack the thread, but how would it affects people’s decisions if a 23” barrel was the only restriction? Barrel life not a huge concern, with good brass being more of interest.
What would a 7-300 Norma push a 180 or 195gr bullet to in that short of a tube? Especially vs the 7 Rem Mag?
I’m guessing it would lose 75 - 100fps over the default 26”

My 7 RemMag barrel is 24" and I can get great velocities, especially with the lighter bullets like the Hornady 139 GMX. I'd like to think the velocity loss would be the same 20-40 fps per inch when going from 26 to 23 with the same load/cartridge.

 

[gnochi]

7 Sherman Short Magnum is within spitting distance of 7saum and fits slightly better into a short action. If you’re planning on wildcatting anyway, I’d go that direction.

Personally, I think I'd go with a 7saum, for hunting applications. Shorter action, shorter bolt throw. The others are long actions. The 7-300 nm will require a larger bolt face and that might push you into are super mag type action. I know my 338nm is on a super mag action and its the parent.
I wouldn't use it for hunting unless it was a stationary position. Basically a canyon gun.

Just my thoughts.
Xdeano

 

[xdeano]

7 Sherman Short Magnum is within spitting distance of 7saum and fits slightly better into a short action. If you’re planning on wildcatting anyway, I’d go that direction.

Nothing wrong with the 7 ssm either.
Xdeano

 

[Just Macca]

For my specific application, it’s for a Blaser R8. Further to that, it’s my intention to rechamber a factory 7x57mm barrel due to it having a 1-8.7 twist (Blasers generally having slow twists).

That basically rules the short mags out, additionally brass can be hard to find in Oz. The more I think on it I think for my very specific niche application, the 7-300 Norma is the go.

Lapua brass, good capacity, I can just find a middle of the road node and hopefully hit 7Rem velocity without torturing the brass. And being a Blaser the action is the same size regardless.

Cheers all.

 

[gnochi]

For my specific application, it’s for a Blaser R8. Further to that, it’s my intention to rechamber a factory 7x57mm barrel due to it having a 1-8.7 twist (Blasers generally having slow twists).

That basically rules the short mags out, additionally brass can be hard to find in Oz. The more I think on it I think for my very specific niche application, the 7-300 Norma is the go.

Lapua brass, good capacity, I can just find a middle of the road node and hopefully hit 7Rem velocity without torturing the brass. And being a Blaser the action is the same size regardless.

Cheers all.

Major red flag - you’ll need a bolt face that’s .590-ish, and your action will need support for the ~1.6x bolt thrust you’ll get from the same pressure on the larger face (vs .474 for the 7x57).

The other issue you’ll see is that you’ll be limited by the pretty short overall cartridge length of the 7x57 of a hair over 3 inches, if your magazine and feed ramp are limited. You might not be able to fit the 3.34 COAL of something like a 7-270 and still feed.

Given that, my recommendations are to do some combination of:

1. Burn out your barrel with 7x57
2. Rebarrel to a tighter twist
3. Pay the gunsmith to alter the magazine (box?) and feed ramps for max COAL of ~3.4 inches, then go 7-270 or 7 Sherman (which in this case is basically 7-270 Ackley Improved)
4. Chop the barrel forwards, re-thread, and go something like 7-08 loaded long

 

[benchmstr]

West Texas Ordnance has a wildcat they make that's a necked down and improved 300 Norma. They're driving 180gr bullets in the 3300 fps range, and 195s to 3200. I have no idea what the barrel life is like, but the ballistics are pretty impressive... https://westtexordnance.com/7mm-300-norma-improved/ - I kinda want one, just because... LOL

At first I was excited by those numbers.....then I ran it through the ballistics calculator....not as impressive as I thought.

It doesn't graph out really any better than factory 300 PRC 225 ELDM

bench

 

[davere]

At first I was excited by those numbers.....then I ran it through the ballistics calculator....not as impressive as I thought.

It doesn't graph out really any better than factory 300 PRC 225 ELDM

bench

Are you sure you ran those numbers right? How far out are you looking? I ran numbers through JBM (225 ELDM at 2800 - which seems to be factory speed for that cartridge, and 180 ELD-M at 3300). At 4000 yards, the PRC requires 118.6 mils of elevation, has 10.8 mils of wind, takes 11 seconds to get there, and carries 252 ft-lbs of energy. The 7-300 Improved takes 86.1 mils of elevation, has 9.1 mils of wind, takes 9.6 seconds to get there, and carries 233 ft-lbs of energy.

That doesn't seem to fall into the range of "doesn't graph out really any better" to me? But maybe I've got the wrong numbers for .300 PRC?

 

[benchmstr]

Are you sure you ran those numbers right? How far out are you looking? I ran numbers through JBM (225 ELDM at 2800 - which seems to be factory speed for that cartridge, and 180 ELD-M at 3300). At 4000 yards, the PRC requires 118.6 mils of elevation, has 10.8 mils of wind, takes 11 seconds to get there, and carries 252 ft-lbs of energy. The 7-300 Improved takes 86.1 mils of elevation, has 9.1 mils of wind, takes 9.6 seconds to get there, and carries 233 ft-lbs of energy.

That doesn't seem to fall into the range of "doesn't graph out really any better" to me? But maybe I've got the wrong numbers for .300 PRC?

Nah, Just looking out to 2000 yards....most shooting beyond that is laughable to me...when people say "I shot 36 rounds and got 4 hits at 4000 yards" it just makes me cringe....as a long range community we need to master 2500 yards and in with non XL calibers instead of pretending 4000 yards is feasible.....

I liken it to powerlifting when a dude bombs out out a 400lb bench, but his next attempt 30 minutes later is 500lbs.....ditch the pride and curiosity and master more realistic limitations before the skill, and technology moves forward....I ultimately believe its the technology that needs to advance more than anything....and its getting there.

bench

 

[fdkay]

7mm LRM might be a decent option.
The only downer is Hornady brass.
You could probably save a bit of cash when you can find .375 ruger brass and neck it down.

 

[Just Macca]

Major red flag - you’ll need a bolt face that’s .590-ish, and your action will need support for the ~1.6x bolt thrust you’ll get from the same pressure on the larger face (vs .474 for the 7x57).

The other issue you’ll see is that you’ll be limited by the pretty short overall cartridge length of the 7x57 of a hair over 3 inches, if your magazine and feed ramp are limited. You might not be able to fit the 3.34 COAL of something like a 7-270 and still feed.

Given that, my recommendations are to do some combination of:

1. Burn out your barrel with 7x57
2. Rebarrel to a tighter twist
3. Pay the gunsmith to alter the magazine (box?) and feed ramps for max COAL of ~3.4 inches, then go 7-270 or 7 Sherman (which in this case is basically 7-270 Ackley Improved)
4. Chop the barrel forwards, re-thread, and go something like 7-08 loaded long

I definitely recognise your concern. And it would t be worth risking in a standard rifle with a basic action and threaded barrel.

But, the Blaser R8 is a switch barrel that accepts 22LR to 338LM. I’d just need to buy the appropriate bolt head and magazine insert. The chamber section of the factory barrel and its contour are all uniform across the various chamberings.

Meaning a 7x57 has the same external dimensions as a 338 LM or 500 Jeffery.

 

[Just Macca]

Also, is there a straight 7-300 Norma which is just necked down with no shoulder angle change? I’ve generally only read about them being improved with no exact shoulder angle listed.

 

[Bradu]

Also, is there a straight 7-300 Norma which is just necked down with no shoulder angle change? I’ve generally only read about them being improved with no exact shoulder angle listed.

I have a regular 7-300 norma, hit max pressure at 3300 fps with a 195 using rl33. I'm running just under 3100 for my reloads. I've only shot it a few times because of not having a range to take advantage of it. I've had it out to a mile with good results but haven't had a chance to attempt it again. A person can get 3100 with a 28 nosler as well but I wanted better brass than what was offered at the time.

 

[Just Macca]

I have a regular 7-300 norma, hit max pressure at 3300 fps with a 195 using rl33. I'm running just under 3100 for my reloads. I've only shot it a few times because of not having a range to take advantage of it. I've had it out to a mile with good results but haven't had a chance to attempt it again. A person can get 3100 with a 28 nosler as well but I wanted better brass than what was offered at the time.

What’s your barrel length? And how many degrees is the shoulder angle? I’m assuming it’s a single pass through your die and load.

 

[davere]

Nah, Just looking out to 2000 yards....most shooting beyond that is laughable to me...when people say "I shot 36 rounds and got 4 hits at 4000 yards" it just makes me cringe....as a long range community we need to master 2500 yards and in with non XL calibers instead of pretending 4000 yards is feasible.....

Since this was the ELR forum, I just took it super long... but at 2k, there's a marked difference between the two. The PRC needs 26.1 mils, where as the 7-300 needs 16.7. 4.6 mils of wind vs 3.3... And the 7-300 is still supersonic at that point, and arrives with about 100 ft-lbs more energy. That still looks like apples and oranges, to me, not "same same".

I agree that super long ELR stuff, and "4 hits for 36 rounds", is not all that practical. It's cool that guys can hit shit out there, and that they're pushing the technology envelope - eventually that knowledge will make it back into cartridge and bullet designs even for short action. But I'm more interested in first round and every round hits.

I'm just saying that I don't get what you mean by these two cartridges looking the same ballistically.

 

[millertime2]

7RM I can get 2950 with Retumbo and 180’s. I really wrestled with building a 7-300WM or the 7-300NM from WTO. It gets to a mile easy as it is and I’m not sure how often I would ever use the extra FPS of the other 2, neat for sure but the regular 7RM really gets it done. I wondered if they would ever make any bullets over 200gr with higher BC’s then I would be interested in the bigger case to get those moving 2950-3000.

 

[Milf Dots]

7RM I can get 2950 with Retumbo and 180’s. I really wrestled with building a 7-300WM or the 7-300NM from WTO. It gets to a mile easy as it is and I’m not sure how often I would ever use the extra FPS of the other 2, neat for sure but the regular 7RM really gets it done. I wondered if they would ever make any bullets over 200gr with higher BC’s then I would be interested in the bigger case to get those moving 2950-3000.

Nice! Newb here with a dumb question- is your COAL still within SAAMI specs, it still feeds from the DBM? Thanks

 

[millertime2]

Currently mine? No I had it throated so I could shoot 180 ELDM’s, 195 EOL loaded long but still fits in the DBM. The rifle had a 24” 1:9 when I got it I could only manage about 2800fps out of it with 180’s. I switched to a 28” 1:8 and I’m a lot happier.

 

[Milf Dots]

Currently mine? No I had it throated so I could shoot 180 ELDM’s, 195 EOL loaded long but still fits in the DBM. The rifle had a 24” 1:9 when I got it I could only manage about 2800fps out of it with 180’s. I switched to a 28” 1:8 and I’m a lot happier.

Cool. I'm a newb, so everytime I'm on SH I learn how much I don't know, and how much more there is to absorb. I'm eventually going to build or have built a rifle in 6.5prc or a 7mm magnum flavor. I'd like to stick with a factory cartridge and not a wildcat, but I'm not sure that's feasible with a 7mm magnum, because I'd like a 7mm magnum rifle to be tailored to a 184-19x gr bullet seated to modern longish style.

I know with the 6.5prc it's a little easier because it's a very modern saami spec, and some factory ammo already uses very heavy for caliber bullets.

 

[Bradu]

What’s your barrel length? And how many degrees is the shoulder angle? I’m assuming it’s a single pass through your die and load.

28", was supposed to be 30" but minor issue. Standard 20⁰ shoulder and I used 3 bushings. You can do one pass if you have a custom full length sizing die made, it's too much for one pass using bushings. Some may disagree but that was my experience.

 

[millertime2]

Cool. I'm a newb, so everytime I'm on SH I learn how much I don't know, and how much more there is to absorb. I'm eventually going to build or have built a rifle in 6.5prc or a 7mm magnum flavor. I'd like to stick with a factory cartridge and not a wildcat, but I'm not sure that's feasible with a 7mm magnum, because I'd like a 7mm magnum rifle to be tailored to a 184-19x gr bullet seated to modern longish style.

I know with the 6.5prc it's a little easier because it's a very modern saami spec, and some factory ammo already uses very heavy for caliber bullets.

Yeah how bout a factory 7 PRC chambered for 195 EOL’s 1:8 twist and factory Berger ammo running 3000 FPS!

 

[Milf Dots]

Yeah how bout a factory 7 PRC chambered for 195 EOL’s 1:8 twist and factory Berger ammo running 3000 FPS!

Take my money!
Berger should do the 7mmPRC before Hornady does. Lapua brass, UNbelted magnum. 195 EOL's at 3000.

 

[Just Macca]

Lapua brass should be the first consideration prior to picking a new cartridge I reckon. And Lapua have a massive hole in their lineup by neglecting the standard magnum.

 

[mram10]

I just sold my 7-300wm reamer after two builds. Definitely had better luck with load development and accuracy over my 7rem mags. Sold the reamer because I went to 28 nosler.

 

[Eshu]

7 Sherman Short Magnum is within spitting distance of 7saum and fits slightly better into a short action. If you’re planning on wildcatting anyway, I’d go that direction.

And then there is the 7mm Sherman max, now you are talkin.